This invention relates to belt drive systems and, more particularly, to riding mowers including a belt drive system.
The drive wheels for self-propelled, riding lawn mowers commonly are driven by a belt drive system including an endless belt trained about a drive pulley and a driven pulley. During operation, one run or side of the belt, referred to as the tight side, is under both dynamic and static tension whereas the other or slack side is under only static tension. If the ratio of dynamic to static tension becomes too great, the belt slips and the drive system becomes inefffective. This condition can be minimized by providing means for automatically increasing the static tension on the belt to the point where slippage does not occur.
A drive system including means for automatically increasing the static tension as the dynamic tension increases is referred to as being self-energizing. Prior self-energizing belt drive systems are self-energizing only in the forward drive mode and not in the reverse drive mode.
Attention is directed to the following U.S. patents relating to belt drive systems:
______________________________________ PATENTEE PATENT NO. ISSUE DATE ______________________________________ Henry 500,069 June 20, 1893 Hill 2,795,254 June 11, 1957 Halls 3,550,463 Dec. 29, 1970 ______________________________________